Command-line variable assignment

1 files changed, 154 insertions, 84 deletions

diff --git a/tools/make.c b/tools/make.c
index 0b1f704..0b82cd0 100644
--- a/tools/make.c
+++ b/tools/make.c
@@ -1,3 +1,9 @@
+/*
+ * This file is part of musl-esp: modified version of Musl libc library.
+ * musl-esp in general and this file specifically are available under
+ * MIT license. See COPYRIGHT file.
+ */
+
 #include "common.h"
 
 enum {
@@ -11,12 +17,6 @@ enum {
 
 const char *debug_prx = ">>> ";
 
-struct conf {
-	char *target;
-	char *makefile;
-	int debug_mode;
-};
-
 struct line {
 	int linenum;
 	struct str str;
@@ -58,9 +58,15 @@ struct rule_details {
 	int lineno;
 };
 
+enum {
+	vs_makefile,
+	vs_cmdargs
+};
+
 struct vt_cell {
 	struct str vname;
 	struct str value;
+	char scope;
 };
 
 struct vtable {
@@ -180,21 +186,21 @@ static struct vt_cell *vtable_getcell(struct vtable *t, struct str *key)
 }
 
 static void vtable_update(struct vtable *vt, struct str *key,
-		int alloc_name, struct str *value)
+		int alloc_name, struct str *value, char scope)
 {
 	struct vt_cell *cell = vtable_getcell(vt, key);
 	if (cell->vname.start == NULL) {
 		++vt->cells_occupied;
 		if ((double)vt->cells_occupied / hash_table_size >= 0.7)
 			error("vtable: threshold reached");
-	}
-	if (cell->vname.start == NULL) {
+
 		if (alloc_name)
 			strdup(&cell->vname, key, 0);
 		else
 			cell->vname = *key;
 	}
 	cell->value = *value;
+	cell->scope = scope;
 }
 
 static struct str *vtable_find(struct vtable *vt, struct str *key)
@@ -233,37 +239,6 @@ static int rtable_find(struct rtable *rt, struct str *key,
 	return 1;
 }
 
-static void parse_cmdargs(struct conf *conf, char **argv)
-{
-	++argv;
-	for (; argv[0]; ++argv) {
-		if (argv[0][0] == '-') {
-			if (argv[0][1] == 'f' && argv[0][2] == 0) {
-				if (argv[1] == NULL)
-					error("-f: missing file name");
-				conf->makefile = argv[1];
-				++argv;
-			} else if (argv[0][1] == 'C' && argv[0][2] == 0) {
-				if (argv[1] == NULL)
-					error("-C: missing dir");
-				if (chdir(argv[1]) == -1)
-					syscall_error(argv[1]);
-				++argv;
-			} else if (argv[0][1] == 'd' && argv[0][2] == 0) {
-				conf->debug_mode = 1;
-			} else {
-				error("%s: unknown flag", argv[0]);
-			}
-		} else {
-			if (conf->target)
-				error("%s: target already provided");
-			conf->target = argv[0];
-		}
-	}
-	if (conf->makefile == NULL)
-		conf->makefile = "Makefile";
-}
-
 static char *mmap_makefile(char *fname)
 {
 	int fd = open(fname, O_RDONLY, 0);
@@ -287,6 +262,15 @@ syserr:
 	return NULL; /* unreachable */
 }
 
+static char *strchr(char *s, char c)
+{
+	for (; *s; ++s) {
+		if (*s == c)
+			return s;
+	}
+	return NULL;
+}
+
 static int readline(char **makefile, struct line *line)
 {
 	static int linenum = 1;
@@ -1724,45 +1708,73 @@ static void make_full_vname(struct buf *dest, struct str *prx,
 	buf_puts(dest, vname);
 }
 
-static void set_single_var(struct vtable *vt, int mode, struct str *prefix,
-	struct str *vname,struct str *value, int alloc_name)
+struct variable {
+	struct str name;
+	struct strbuf *goals;
+	struct str *value;
+	char scope;
+
+	int linenum;
+	struct vtable *vt;
+};
+
+static int check_policy(struct variable *var, struct str *name)
+{
+	struct vt_cell *cell = vtable_getcell(var->vt, name);
+	if (cell->vname.start == NULL)
+		return 1;
+
+	if (var->scope == vs_makefile) {
+		if (cell->scope == vs_makefile)
+			lerror(var->linenum, "%S: variable redefinition",
+				name);
+		return 0;
+	}
+	return 1;
+}
+
+static void set_single_var(struct variable *var, struct str *goal, int mode)
 {
 	static char localbuf[buf_static_size];
 	struct buf buf;
-	struct str tmp;
+	struct str fullname;
+	/* TODO: Why do we need to alloc for goal specific assignments */
+	int alloc = goal ? 1 : 0;
 
 	buf_static_init(buf, localbuf, buf_static_size);
 
-	if (prefix != NULL) {
-		make_full_vname(&buf, prefix, vname);
-		tmp = (struct str) { buf.start, buf.cur };
+	if (goal != NULL) {
+		make_full_vname(&buf, goal, &var->name);
+		fullname = (struct str) { buf.start, buf.cur };
 	} else {
-		tmp = *vname;
+		fullname = var->name;
 	}
+
 	if (mode == svmode_set) {
-		vtable_update(vt, &tmp, alloc_name, value);
+		if (check_policy(var, &fullname) == 0)
+			return;
+		/* Double work, but I do not think we should even bother */
+		vtable_update(var->vt, &fullname, alloc, var->value, var->scope);
 	} else {
 		struct str newval;
-		struct str *oldval = vtable_find(vt, &tmp);
+		struct str *oldval = vtable_find(var->vt, &fullname);
 		if (oldval == NULL)
-			oldval = vtable_find(vt, vname);
-		str_combine(&newval, oldval, value);
-		vtable_update(vt, &tmp, alloc_name, &newval);
+			oldval = vtable_find(var->vt, &var->name);
+		str_combine(&newval, oldval, var->value);
+		vtable_update(var->vt, &fullname, alloc, &newval, var->scope);
 	}
 }
 
-static void setvar(struct vtable *vt, int mode, struct strbuf *targets,
-		struct str *vname, struct str *value)
+static void setvar(struct variable *var, int mode)
 {
-	trim(value);
+	trim(var->value);
 
-	if (targets != NULL) {
+	if (var->goals != NULL) {
 		int i;
-		for (i = 0; i < targets->len; ++i) {
-			set_single_var(vt, mode, &targets->buf[i].str, vname, value, 1);
-		}
+		for (i = 0; i < var->goals->len; ++i)
+			set_single_var(var, &var->goals->buf[i].str, mode);
 	} else {
-		set_single_var(vt, mode, NULL, vname, value, 0);
+		set_single_var(var, NULL, mode);
 	}
 }
 
@@ -1773,32 +1785,37 @@ static int is_followed(struct line *line, char c)
 
 static void follows(struct line *line, char c)
 {
-	if (is_followed(line, c)) {
-		line->str.start += 2;
+	if (is_followed(line, c))
 		return;
-	}
 	lerror(line->linenum, "expected %c after %c", c,
 		line->str.start[0]);
 }
 
-static void parse_assignment(struct world *world, struct strbuf *targets,
-		struct buf *buf, struct line *line)
+static void parse_assignment(struct world *world, struct strbuf *goals,
+		struct buf *buf, struct line *line, char scope)
 {
-	struct str vname = { buf->start, buf->cur };
+	struct variable var = {
+		{ buf->start, buf->cur },
+		goals,
+		&line->str,
+		scope,
+
+		line->linenum,
+		&world->vtable
+	};
 
-	trim(&vname);
-	if (!valid_var_name(&vname)) {
+	trim(&var.name);
+	if (!valid_var_name(&var.name)) {
 		lerror(line->linenum, "[%S]: invalid variable name",
-			&vname);
+			&var.name);
 	}
-	if (line->str.start[0] == '+') {
+	if (var.value->start[0] == '+') {
 		follows(line, '=');
-		setvar(&world->vtable, svmode_append, targets, &vname,
-				&line->str);
+		var.value->start += 2;
+		setvar(&var, svmode_append);
 	} else {
-		++line->str.start;
-		setvar(&world->vtable, svmode_set, targets, &vname,
-				&line->str);
+		++var.value->start;
+		setvar(&var, svmode_set);
 	}
 }
 
@@ -1975,7 +1992,7 @@ static void handle_target_spec(struct world *world, struct buf *buf,
 	if (*line->str.start == ':')
 		lerror(line->linenum, "expected target-specific var");
 
-	parse_assignment(world, &rule->targets, buf, line);
+	parse_assignment(world, &rule->targets, buf, line, vs_makefile);
 }
 
 static void parse_rule(struct world *world, struct buf *buf,
@@ -2016,7 +2033,7 @@ static int parse_toplev(struct world *world)
 	} else if (*line.str.start == ':') {
 		parse_rule(world, buf, &line);
 	} else {
-		parse_assignment(world, NULL, buf, &line);
+		parse_assignment(world, NULL, buf, &line, vs_makefile);
 	}
 	return 1;
 }
@@ -2027,14 +2044,11 @@ static void parse(struct world *world)
 		;
 }
 
-static void world_init(struct world *world, struct conf *conf, char **envp)
+static void world_init(struct world *world, char **envp)
 {
-	world->makefile = mmap_makefile(conf->makefile);
-	world->target = conf->target ? STR(conf->target) : CSTR("");
 	world->envp = envp;
 
 	world->pat_rule_num = 0;
-	world->debug_mode = conf->debug_mode;
 
 	vtable_init(&world->vtable);
 	rtable_init(&world->rtable);
@@ -2427,6 +2441,63 @@ static void exec(struct world *world)
 	exec_target(world, &world->target, &info);
 }
 
+static int is_assignment(char *arg, char **equal_sign)
+{
+	char *tmp = strchr(arg, '=');
+	if (tmp == NULL)
+		return 0;
+	*equal_sign = tmp;
+	return 1;
+}
+
+static void parse_cmdarg_assignment(struct world *world, char *arg,
+	char *equal_sign)
+{
+	struct buf buf = { arg, equal_sign, equal_sign };
+	char *end = equal_sign + strzlen(equal_sign);
+	struct line line = { 0, { equal_sign, end } };
+
+	parse_assignment(world, NULL, &buf, &line, vs_cmdargs);
+}
+
+static void parse_cmdargs(struct world *world, char **argv)
+{
+	char *makefile = "Makefile";
+	char *target = NULL;
+	char *equal_sign;
+
+	++argv;
+	for (; argv[0]; ++argv) {
+		if (argv[0][0] == '-') {
+			if (argv[0][1] == 'f' && argv[0][2] == 0) {
+				if (argv[1] == NULL)
+					error("-f: missing file name");
+				makefile = argv[1];
+				++argv;
+			} else if (argv[0][1] == 'C' && argv[0][2] == 0) {
+				if (argv[1] == NULL)
+					error("-C: missing dir");
+				if (chdir(argv[1]) == -1)
+					syscall_error(argv[1]);
+				++argv;
+			} else if (argv[0][1] == 'd' && argv[0][2] == 0) {
+				world->debug_mode = 1;
+			} else {
+				error("%s: unknown flag", argv[0]);
+			}
+		} else if (is_assignment(argv[0], &equal_sign)) {
+			parse_cmdarg_assignment(world, argv[0],
+				equal_sign);
+		} else {
+			if (target)
+				error("%s: target already provided");
+			target = argv[0];
+		}
+	}
+	world->makefile = mmap_makefile(makefile);
+	world->target = target ? STR(target) : CSTR("");
+}
+
 static void print_program_time(int debug)
 {
 	struct rusage rusage;
@@ -2442,11 +2513,10 @@ static void print_program_time(int debug)
 int main(int argc, char **argv, char **envp)
 {
 	struct world world;
-	struct conf conf = { NULL, NULL };
 
-	parse_cmdargs(&conf, argv);
+	world_init(&world, envp);
+	parse_cmdargs(&world, argv);
 
-	world_init(&world, &conf, envp);
 	parse(&world);
 
 	exec(&world);